A leading union has spoken of its "shock" after claiming to have discovered plans for a "substantial" cut in the number of lock and weir keepers along the River Thames.

The GMB said the Environment Agency will put forward proposals in March to cut 90 residential keepers dealing with locks, sluices and weirs.

The Thames has been badly hit by flooding in recent weeks, with many communities still dealing with the effects of the river bursting its banks.

The new losses would be on top of 1,700 job losses already being planned by the agency, said the GMB.

Officials said a freeze on recruitment of residential keepers will also be proposed, warning this would increase the risk of flooding and put lioves and property at risk.

Regional officer Frank Minal said: "With the River Thames flooded, and just a week after the EA chief executive assured the Government that there would be no cuts to front line flood defences as part of the proposed 1,700 job cuts, we are shocked to learn of plans to table a report in March with plans to cut 90 residential keepers.

"These unnecessary changes will see the response time to operate weirs and sluices increase from minutes to hours."

An EA statement said: "Our budget for 2014/15 will be confirmed shortly. However, we are likely to reduce staff numbers from the previous forecast of around 11,250 at the end of March 2014 to around 9,700 by October 2014.

"We will then aim to keep numbers broadly at that level through to March 2015 dependent of course on future funding.

"The planned reductions in posts will not affect the Environment Agency's ability to respond to flooding incidents and the Environment Agency will minimise the impact on other front line services through the changes.

"The detail of how different teams within the Environment Agency will be affected is not yet finalised so we will not comment further, but union, staff and customer engagement is planned across the Environment Agency over the coming months."